Centrifugal machine



A. H. GIBSON.

CENTRIFUGAL MACHINE.

APPLICATION FlLED APR.2I, 1915. RENEWED JUNE 25.1919.

Patented Apr. 13,1920.

ANGUS H. GIBSON, 0F SALT LAKE CITY, UTAH.

GENTRIFUGAL MACHINE.

Application filed April 21,1915, Serial No. 22,793.

To all whom z'tmay concern:

Be it known that I, ANeUs H. GIBsoN, citizen of the United States, and resident of Salt Lake City, Utah, have invented certain new and useful Improvements in Centrifugal Machines, of which the following is a specification. 7

This invention relates to centrifugal machines of the type commonly usedin sugar refineries and is intended to provide a convenient and efficient construction by which the sugar accumulated on the interior of the centrifugal basket may be elliciently and quickly discharged by the automatic operation of the machine after each charge of sugar has been purified by centrifugal action and washed in the usual manner.

To this end the invention combination with the rotary basket and its shaft of a vertically movable bottom connected with actuating mechanism by which the bottom is lowered automatically by the braking or slowing down of the machine.

In the accompanying drawings I have illustrated a simple and convenient form of mechanism for effecting the discharge of the sugar upon the principle referred to.

Figure 1 is aside elevation in vertical section of the well-known type of sugar centrifugal machine equipped with my invention. Y

Fig. 2 is a plan view partly broken away to show underlying portions.

Fig. 3 isan enlarged detail view of the lower p0rtion=of the basket in vertical section.

The invention herein is shown as applied to a well-known type of sugar centrifugal machine comprising a gyratory shaft a rotatably suspended in an oscillatory. head a' which is mounted in the fixed hanger a, the shaft being driven by any suitable means, as by a driving pulley o inside of which issh'own a well-known type of eX- pansible brake a The centrifugal basket comprises the perforated cylindrical Wall Z) properly reinforced and secured at its lower end to a I strong ring Z2 which is preferably cast integral with the supporting spider b which is provided with concentrically arranged upwardly extending supporting arms 6 between which are left large peripheral openings for'the escape'of' the sugar outward when it is discharged fromthe'basket. The spid'er'hasja'- central hub b by-"which it is Specification of Letters Patent.

comprises the Patented Apr. 13, 1920. Renewed June 25, 1919. Serial No. 306,715.

rigidly secured to the lower end of the shaft a.

The basket has the usual top rim 6 but its lower end is dur ng the operation of the with a depending rabbeted flange 0 which makes a tight or close joint With thellower edge portion of the basket when in raised or closed position. The is connected by means of a cone or spider c with a supporting and actuating sleeve 0 which surrounds the basket shaft a, said sleeve 0 being provided with an external screw-thread.

he raising and lowering member herein mounted upon a thrust or bearing collar 05 secured to the shaft so as to permit rotative movement of the sleeve d in relation shaft. An

minish friction. The sleeve (2 is internally screw-threaded, as shown at dflto engage the exterior thread on the bottom supporting sleeve 0 These engaging screw-threads of the actuating member (Z and the supporting sleeve 0 are so formed that in starting the machine in operation any tendency on the part of member (Z, d to lag behind the shaft serves to raise the sleeve 0 and the movable bottom 0 and so that when the brake is applied to the shaft a, the momentum of the bottom actuating member d causes said member to continue its rotation at a higher speed than the rotation of the basket shaft when slowed down by the brake and therefore depresses or lowers the movable bottom 0 to its lowermost positionbelow the peripheral openings in the spider b 6.

After the basket has been emptied while the machine is being brought up to normal speed a brake e mounted on a bracket 6 above the curb f is pushed into braking engagement with the wheel d so as to retard the sleeve d in relation to the basket shaft and thereby raise the bottom a into its uppermost or closing position. This brake is normally kept out of engagement with the wheel d by a spring 6 In order to assist in guiding the movable bottom, I provide inwardly projecting ribs; (7) on the spider arms 72*, and on the under side of the bottom 0 at its periphery, I so anti-friction thrust beanng, as shown at (Z may be used to diable bottom and the basket spider while at tracted syrup which cure a series of brackets 0 each carrying a pair of slightly spaced anti-friction rollers 0 arranged to engage the opposite faces of the guide rib 5 The conical connecting spider 0 may also be provided with a down wardly extending tubular collar 0 engaging the upwardly extending cylindrical portion 6 of the spider izing guiding means to prevent the sleeve c 'from binding upon the basket shaft. The antifrictien rollers serve to prevent any binding engagement between the movthe same time securing their rotation in perfect unison.

To secure a tight joint between the bottom c and the lower edge of the basket I prefer to form the loweredge of the basket with a tapered or connecting edge, as shown at I), to shear off any sugar that may collect in the rabbeted edge of the movable bottom. Since the pressure of the syrup and the sugar against the wall of the basket during the centrifugal separation is very great, I provide for draining the joint between the basket and the movable bottom by scoring an annular groove 6 on the inside of the basket near its lower edge and providing a series of'perforations running from this groove out through. the ring 6 as shown at 'b.

To assist in breaking up sugar when the bottom is lowered for discharging purposes, I provide a series of hooked arms or sugar-engaging members g which are pivotally connected with brackets g secured to the bottom 0. The hooks or heads 9 at the upper end are embedded in the sugar wall and act as a sort of hoe to pull down the sugar when the bottom is lowered. The sugar-engaging members will remain normally against the peripheral wall of the basket, owing to centrifugal force. They are prevented from falling inward by angularly projecting feet 9 The basket curb f is provided with an annular trough f in position to catch the exflows down outside of the flange ring 6 The inner wall of this trough is also positioned to serve as a defiector to throw sugar downward into a hopper or receptacle beneath the curb.

It will be seen that the discharge of the sugar is effected automatically when stopping the machine in the usual way without extra effort or labor on the part of the attendant," and that the discharge is effected almost instantaneously by centrifugal action; while there is' nothing to interfere either with the inspection of the interior of the basket or with the washing operation before the sugar is discharged.

What I claim is:

1. In a centrifugal machine the combination'with a rotary shaft and a centrifugal basket secured thereto, a

hub to serve as centraldown the wallcdvertically movable bottom for sustalning the solid matter as it accumulates in the basket, means for raising and lowering said movable bottom to close and to open respectively the lower end of the basket, said means being actuated automatically by the slowing down of the basket, substantially as described.

2. In a centrifugal machine the suspended rotary shaft, a'centrifugal basket I secured to the lower end thereof, a vertically movable bottom arranged to normally close the lower end of the basket to sup-v port the solid content, a vertically movable sleeve surrounding the shaft and. connected with the movable bottom, and means for engaging said sleeve and actuated by the momentum of rotation to lower the sleeve and the bottom when the rotation of the shaft. is retarded, substantially as described. I e

3. The combination with a suspended gyratory shaft, a centrifugal basket secured to the lower end thereof, avertically movable circular bottom plate arranged to close the lower end of the basket during the normal operation of the machine, a supporting member extending upwardly" around the shaft and connected with said bottom, and an actuating member rotatably mounted on the shaft and having operative connection with said supporting member to lower said supporting member when rotating at a faster speed thanthe rotation of the basket shaft, substantially as described.

4:. In a centrifugal machine the combination of the suspended rotary shaft, a centrifugal basket secured to the lower end thereof, a vertically movable bottom arranged to close th lower end of the basket during the normal operation of the machine, a screw-threadedslide sleeve mounted on the shaft and connected with the bottom, a cooperating actuating member loosely mounted on the shaft soas to be rotatable at a different rateof speed in order to move said bottom vertically, substantially as described. 7

5. The combination with a rotary centrifugal basket and its. central driving shaft, a vertically movable bottom arranged to close the open lower end of said basket, an actuating member 'rotatably mounted on said shaft, means ing the bottom with said actuating member, means for retarding the basket shaft, and means for retarding member whereby through a'diiferential rofor operatively connect- 7 said actuating tation of the actuating member in relation bottom arranged when raised to close the lower end of the basket, means for operatively connecting said-rotatable sleeve with the movable bottom, said means acting to lower the bottom when the sleeve is rotating faster than the basket shaft and to raise the bottom when said sleeve rotates slower than the basket shaft, substantially as described.

7. The combination of a rotary shaft suspended from an overhead support, a centrilugal basket securedto its lower end, a vertically movable bottom arranged to normally close the lower end of the basket, means mounted on the shaft between the basket and the overhead support to raise and lower said bottom automatically by the differential rotation of the basket and said raising and lowering means, and upwardly extended members connected with said bottom to engage and pull down the wall of sugar when the bottom is lowered, substantially as described.

8. The combination of the centrifugal basket rotatably suspended from an overhead support, a vertically movable bottom arranged to normally close the lower end of the basket, upwardly extending arms pivotally connected with the bottom and having their upper ends normally resting against the peripheral wall of the basket, and automatically operated means mounted on and normally rotating with the centrifugal basket for lowering the bottom to per- Init the discharge of the solid content when the rotation of the basket is retarded, substantially as described.

9. The combination with the central driving shaft of a basket-supporting spider whose arms are extended upwardly at their outer ends, a peripheral basket screen mounted upon the upper ends of said arms and provided near its lower edge with an annular groove having outlet perforations extending to the outside of the basket, a vertically movable bottom having a flanged periphery constructed to fit into the lower edge of the basket beyond said annular groove, and means for raising and lowering said bottom to permit the discharge of the solid content, substantially as described.

10. A self-discharging centrifugal ma chine embracing in its construction a central driving and supporting shaft, a centrifugal basket structure comprising a peripheral member, and a cooperating bottom member, both supported by said shaft, one of said members being vertically movable in relation to the other, to separate them for discharging purposes, and means automatically operated by the rotation of the machine, to separate the vtwo members, substantially as described.

In witness whereof, I have subscribed the above specification.

ANGUS H. GIBSON. 

